In the past decade, there have been significant advances in development of neurotechnology to stimulate neural and muscle tissue to replace lost function due to neurological disability or neutoruma. For example, there are commercially available systems for deep brain stimulation to treat symptoms of Parkinson's disease and other neuromotor and neuropsychological diseases; vagal nerve stimulation for treating some types if intractable epilepsies and depression, gastric stimulation for gastroparesis, stimulation of the peroneal nerve for foot drop, sacral nerve stimulation for urinary urge incontinence and incontinence, pacing of respiratory and abdominal muscles for respiratory insufficiency, and treatment of unmanageable and pathological pain in various sites of the body.
Most often, a single lead is used to target a single stimulation site, for example for vagal nerve stimulation. Here, there is a single electrode contact site connected via the lead to a stimulating device. In some instances a single lead contains multiple electrode contacts in concentric circles along its longitudinal axis placed at a pre-determined distances. Such a lead is used to stimulate close but longitudinally spatially separated excitable neural tissue, for example, for deep brain stimulation for treating Parkinson's disease spinal cord stimulation for pain management and inner ear (cochlear) stimulation for treating hearing loss. Since, in all of the above multi-electrode lead configurations the contacts are placed on an inseparable substrate at a predetermined distance, they cannot be used for stimulating multiple sites that are spatially distributed over a large 2-dimensional area such as for gastric stimulation.
Additionally, for some functional outcomes, multiple nerve or muscle tissues may have to be stimulated in a coordinated manner to achieve the best functional outcome. For example, for restoring respiration in high quadriplegic subjects and in other respiratory disorders, along with phrenic nerve multiple muscles that are spatially distributed need to be stimulated. In gastroparesis and in other gastric disorders, spatially distributed muscles and nerve endings need to be stimulated and/their activity needs to be sensed.
In addition, there have been attempts to provide sensory feedback to upper extremity amputees by stimulation of the peripheral nerves. Such peripheral nerve stimulation will also require multiple nerves to be targeted to provide information about multiple sensory sources and modalities to the amputee. In order to develop the next generation of neural driven prostheses for amputees, it will also be necessary to record multiple motor intents by recording from different sites, for example different peripheral nerves or muscle tissues. Some specific examples are discussed briefly hereinafter.
MedImplant Patent OS-PS330342, from September 1976, shows a system with a coiled lead of multiple connecting elements partially encased and then each individual connecting element is left free. Each individual connecting element is coiled. No protective bundling method is revealed.
U.S. Pat. No. 7,983,755 shows multisite gastric stimulation with multiple leads (Fig #4). However, U.S. Pat. No. 7,983,755 does not present a method for packaging such leads.
U.S. Pat. No. 5,690,691 shows multisite gastric stimulation with multiple lead. However, U.S. Pat. No. 5,690,691 does not present a method for packaging such leads.
U.S. Pat. No. 7,967,817 refers to a multi-electrode lead containing multiple electrode contacts in concentric circles along its longitudinal axis placed at a pre-determined distances.
U.S. Pat. No. 6,505,075 is an example for peripheral nerve stimulation to treat pain using longitudinal circular multi-contact lead.
U.S. Pat. No. 3,699,956 describes a percutaneous lead that provides fixation and minimizes bacterial penetration.
U.S. Patent Application Publication No. 2007/0255369 describes a percutaneous lead with flaps acting as anchors.
U.S. Pat. No. 4,934,368 describes two nerve cuff electrodes as a separate leads.
There is a need for a multi-electrode lead with separable electrode contacts to target nerve or muscle tissues that are spatially distributed over a large area.